Subsea completion annulus monitoring and bleed down system

Abstract

A subsea wellhead ( 10 ) includes annulus pressure monitoring and bleed down ports ( 32, 34, 36 ) whereby excessive pressure may be detected and bled off to a production controls or workover controls system via an electro/hydraulic jumper ( 58 ). A valve block ( 44 ) bolted to the wellhead ( 10 ) includes pressure transducers ( 52, 54, 56 ) and isolation valves ( 46, 48, 50 ). Excessive annulus pressures and hence damage to the completion program may thereby be avoided in HPHT subsea well applications.

What is claimed is:  
     
       1. A subsea wellhead comprising at least one port extending completely through a side wall of the wellhead and having an interior end connected to a well annulus and an exterior end removably connectable to a jumper which in turn is connected to a controls system; wherein pressure signals and/or expelled annulus fluid may be conveyed from the well annulus to the controls system. 
     
     
       2. A wellhead as defined in  claim 1 , further comprising an isolation valve for controlling flow through the port. 
     
     
       3. A wellhead as defined in  claim 2 , wherein the isolation valve is disposed in a valve block attached to the wellhead. 
     
     
       4. A wellhead as defined in  claim 3 , wherein the valve block comprise an ROV panel. 
     
     
       5. A wellhead as defined in  claim 4 , wherein the ROV panel comprises a receptacle for actuation of the isolation valve. 
     
     
       6. A wellhead as defined in  claim 1 , further comprising a pressure transducer in communication with the port. 
     
     
       7. A wellhead as defined in  claim 6 , wherein a signal from the pressure transducer is conveyed to the controls system via the jumper. 
     
     
       8. A wellhead as defined in  claim 4 , wherein the ROV panel comprises a number of electrical and/or hydraulic couplers for connection to the jumper. 
     
     
       9. In combination with a wellhead as defined in  claim 1 , a horizontal Christmas tree which is mounted on the wellhead. 
     
     
       10. A wellhead as defined in  claim 9 , wherein the horizontal Christmas tree is a drill-through horizontal Christmas tree.